1. Field of the Invention
This invention relates generally to sights for archery bows and, more specifically, to bow sights having sight pin constructions that are pre-set for a particular bow so as to reduce the amount of adjustment necessary to sight in the bow sight to the bow.
2. Description of the Art
Archery bow sights utilizing a plurality of sight pins have been known in the art for many years. Typically, these sights use a bracket or other mounting structure for mounting the sight to a bow. The sight is commonly comprised of a pin plate, a pin guard, and a plurality of sight pins which are secured to the pin plate and extend into a sight window formed by the pin guard. The sight is mounted to a bow in a manner so that when the bow string is drawn, the archer can look through a peep sight provided in the bow string and align the tip of a pin attached to the sight with a target. For sights utilizing a plurality of sight pins having their tips vertically aligned, each individual sight pin is typically provided for aiming the bow at a target at a particular distance from the archer. For example, one pin may be positioned in the sight for aiming the bow at a target 50 yards from the archer while another pin may be positioned for a target that is at 70 yards distance.
An example of a bow sight known in the art is illustrated in FIG. 1 in which a bow sighting device 10 is connected to an archery bow 12. The sighting device 10 is comprised of a pin plate 14, a pin guard 16 and a sight window 18 formed therebetween. A plurality of sight pins 20 are secured to the pin plate 14 by attachment members 22, such as screws, which engage the sight pins 20 and extend through a slot 24 formed in the pin plate 14. The sight pins 20 extend transversely from the pin plate 14 into the sight window 18. The sighting device 10 is attached to a first bracket 28 by securement members 30. The first bracket 28 may be adjustably connected to a second bracket 32 by securement members 34, and the second bracket 32 may be adjustable secured to a third bracket 36 by screw members 38, which attach it to the bow 12.
In use, the archer typically aligns a peep sight positioned on or formed in the bowstring with one of the sight pins 20. In order to properly sight in the sight to the bow (i.e., properly adjust sight pin to a particular distance from the target), each of the sight pins 20 is individually positioned and adjusted to correspond to a given distance (e.g., 20 yards, 40 yards, 60 yards, etc.) from the bow 12. The sight pins 20 allow the archer to better position the aim of the arrow to compensate for target distance and trajectory. Thus, the archer must position him/herself a specific distance from the target (e.g., 20 yards) and shoot several arrows at the target while adjusting the 20 yard sight pin until the position of the 20 yard sight pin corresponds to arrows hitting the center of the target.
The same procedure is repeated for each of the other sight pins (e.g., 30 yard pin, 40 yard pin, 50 yard pin, etc.). In most cases, upon repeated shooting, the sight pins can be fairly closely positioned relative to the bow sight at positions that provide acceptable targeting. As the distance from the target increases, however, it becomes increasingly more difficult to sight in the pins as the shooters ability to hold the bow steady during targeting becomes more important. That is, at close range, slight movement of the bow during a shot will have less effect on the arrows trajectory relative to the target than will similar movements at long range. Thus, while the error of the position of each sight pin may be approximately equal, such errors are not as detrimental at close range, but are exacerbated as the distance-to-target increases.
Some bow sights provide a single sight pin. Such single pin bow sights are provided for target practice where the distance from the target does not change. Single pin bow sights are also used in sights commonly referred to as pendulum sights that are used in conjunction with tree stands and the like where the hunter is positioned above the target and is aiming in a severely downward direction at the ground to animals below the hunter. In such a situation, the distance to target, while not fixed, is usually within a small range thus suited for a single pin sight arrangement.
Once a single pin sight is adjusted for a particular distance-to-target, the sight is not suited for being used at other ranges. It would be desirable, however, to provide a fixed pin arrangement that can also be used at other ranges without requiring adjustment or re-sighting of the sight pin to accommodate such other distances-to-target. In addition, it would be advantageous to provide a single sight pin structure having multiple sight points configured for attachment to conventional type bow sights.
Accordingly, a fixed pin bow sight is comprised of a bow sight having an attachment portion, a sight pin mounting portion and a sight pin having a plurality of sight tips on said sight pin. Each of the sight tips are predisposed on the sight pin and spaced to provide accurate targeting of an arrow shot from a bow having a particular shooting speed. The spacing between sight tips is defined by the desired targeting distances from the bow. For example, the uppermost sight tip may be configured for a target that is twenty yards away with subsequent sight tips provided for ten yard increments (e.g., 30, 40, 50 and 60 yards). The sight tips are configured to be vertically aligned relative to the ground when firing the bow so that as the distance from target is increased the appropriate sight tip moves from top to bottom of the sight pin.
Another important aspect of the present invention is to ensure that the distance from the sight tips to the peep sight, which is dependent upon the draw of the bow is at a predetermined distance. That is, in order to make the sight tips accurate representations of the target at various distances, the distance from the sight tips to the eye of the archer is factored into the formation of the distance between adjacent sight tips. Because many bows having different draw lengths that may be customized to the archer, the sight also includes brackets or other attachment features that allows the sight to be adjusted either toward or away from the eye of the user at full draw of the bow in order to be positioned at the optimal distance.
In one embodiment, the distance between the sight tips and the peep sight is approximately 26.5 inches. The spacing between sight tips are determined in part based upon this 26.4 inch distance. In order to provide precise sighting of the sight pins for a given bow speed, the distance between sight tips is based upon a peep sight to sight tip distance of approximately 26.4 inches. Such accuracy, however, is not necessary for most practical purposes such as hunting. After the first or uppermost sight tip is sighted in, the remaining sight pins will relatively accurately reflect the other given distances to target. That is, even if the distance from the sight tips to the peep sight is something other than 26.4 inches, such variations in the sight tips to peep sight distance may only have an inch or two difference in the accuracy of the sight tips for a given distance to target. Such variation in accuracy (e.g., one to two or more inches) will still likely accomplish a hit in a vital organ of an animal. Thus, in practicality, the sight may be fixed relative to the bow and not necessarily adjustable thereto in a direction relative to the peep sight given the fact that most bows have a draw at or near about 26 inches.
The spacing between sight tips is calculated using conventional ballistic formulas. Such formulas can be found in an article entitled xe2x80x9cExterior Ballistics of Bows and Arrowsxe2x80x9d by W. J. Rheingans, herein incorporated by this reference. Unlike conventional multiple pin bow sights which require each sight pin to be individually sighted, the bow sight of the present invention only requires sighting in of one of the sight tips. Once one of the sight tips is properly sighted to a target at the appropriate distance for the particular sight tip, the remaining sight tips are automatically sighted in.
In order to sight in the sight pin of the present invention, the bow sight is attached to the riser of the bow and adjusted so that the sight pin will be a particular distance from the peep sight on the bow string. The bow sight is then adjusted to provide proper targeting of a target that is a distance corresponding to the sight tip. For example, if the top sight tip is configured for a distance-to-target of 20 yards, the archer can position him/herself 20 yards from the target and shoot arrows at the target. The position of the sight relative to the riser or the position of the sight pin relative to the sight can then be adjusted vertically or horizontally as required to properly sight in the first sight tip. Once, the first sight tip is set, the remaining sight tips are automatically sighted in as they are fixed relative to the first sight tip.
The sight pin of the present invention may be integrally formed with the sight or may be a separate component that is attached to the sight.
In the case where the sight pin is a separate component, the sight pin may be configured to fit into conventional type bow sights that utilize multiple sight pins. As such, the sight pin of the present invention may be configured to replace conventional sight pins without requiring replacement of the entire sight in order to utilize the novel features of the present invention.
The sight pin of the present invention is further configured to match the shooting speed of the bow. For example, some bows shoot at 250 feet per second while others will shoot at 280 feet per second. The speed of the bow can be easily determined by standard bow speed calculation equipment. In addition, most compound type bows allow for adjustment of the bow speed. Thus, sights or sight pins in accordance with the present invention can be configured to a few standardized bow speeds and the bow adjusted to match the sight or sight pin.
In one embodiment, the sight pin is comprised of a vertical element having a plurality of fiber optic elements coupled to the sight pin each at a particular position along the height of the sight pin. The fiber optic elements extend from the sight pin through the pin guard of the sight, wrap around a portion of the pin guard and are attached to the pin guard at another location. By increasing the length of the fiber optic elements, their individual exposure to ambient light is increased to help increase the brightness of each sight tip.
In another embodiment, the sight pin is configured to mate with a sight in a more conventional fashion by mating with a slot in the pin plate of the sight. A plurality of sight pins are fixed relative to a mounting portion with each of the sight pins coupled or mounted to a single mounting structure.
In another embodiment, the sight pin is configured to mate with a conventional type bow sight but includes a single vertical pin horizontally supported with a mounting structure. If fiber optic sighting elements are utilized, the fiber optic members may have various configurations that expose a portion of their length to ambient light in order to increase their brightness for viewing by the archer.
By providing a sight pin with multiple sight tips in a pre-configured arrangement, the sight tips can be relatively precisely (within manufacturing tolerances) placed along the sight pin at the appropriate locations. Such a configuration is vastly more accurate than requiring the user to sight in each individual sight pin relative to the sight where such pins can be off from the correct position by orders of magnitude greater than that which can be achieved through manufacturing.